The SMOFIL pressurization kit is a simple and reliable system to create a positive pressure inside a smoke-proof filter with respect to that existing in the environment at risk of fire. Ministerial Decree 30-11-83 and Ministerial Decree of 3 August 2015 (the new Consolidated Law) prescribe an overpressure in the filter of at least 0.30 mbar (30 Pa). The SMOFIL kit, thanks to the power of the electric fans used, is able to reach this ΔP value in a very short time, even less than 1 second. In the absence of mains current, during the certified test, it maintained the overpressure in the filter above 0.30 mbar for a time close to 3 hours. The SMOFIL kit is standard equipped with a safety device consisting of a programmable "pressure switch" differential pressure switch that stops the electric fan in the event that the pressure inside the filter reaches values beyond those allowed for easy opening of the doors for the purpose of exodus and reactivating it as soon as the pressure decreases by at least 0.20 mbar (UNI EN 12101.6 standard and Consolidated Fire Prevention Text DM 3-8-2015). A delivery nozzle with adjustable fins allows the regulation of the air flow. The system provides for an internal installation and protected from atmospheric agents. The selection, location and quantity of SMOFIL required are the responsibility and responsibility of the designer of the fire prevention and control system.